Instruction manual

Type MR105
14
alignment. Do not loosen the bonnet thread to align
the pipe holes. Always tighten the bonnet to make
alignment for the control line.
Note
Position the bonnet (key 61) such




located 90° from the valve body ends.
Note
Exercise care to ensure that the actuator

bonnet bore without pinching, cutting or

15. Lubricate the cap screws (key 65) and use it to
position and secure the lower diaphragm casing
(key 62) and internal stiffener plate (key 84) to
the bonnet (key 61). Tighten the cap screws to a
torque of 10 to 12 ft-lbs / 14 to 16 N•m.
16. The serrated side of the lower diaphragm head
(key 53) should be facing up toward the threaded
end of the actuator stem (key 40). Carefully install
the lower diaphragm head over the actuator stem.
Note
Exercise care to ensure that the

the lower diaphragm head bore without
pinching, cutting or damaging in any
way the lower diaphragm head O-ring
(key 51).
17. Place the diaphragm (key 56) over the actuator
stem (key 40) and on top of the lower diaphragm
head (key 53). The convolutions of the diaphragm
should be pointing up.
18. Place the following over the actuator stem
(key 40) and on top of the diaphragm (key 56),
in the following order: diaphragm plate (key 55),
lower spring guide (key 52) and Belleville spring
washer (key 49). The raised inner diameter of the
Belleville spring washer should be pointing toward
the threaded end of the actuator stem.
19. Lubricate the threads of the actuator stem (key 40)
and thread the two jam nuts (key 48) onto it.
Using wrench ats, hold the stem and torque the
jam nuts individually. Tighten to a torque of 12 to
14 ft-lbs / 16 to 19 N•m.
Note
For pressure-loaded actuator option skip

with upper casing welding assembly

20. Install the upper diaphragm casing (key 63)
or spring case spacer (key 66) assembly
while aligning the bolt circle holes in the upper
diaphragm casing, diaphragm (key 56) and lower
diaphragm casing (key 62).
Note
Exercise care to ensure that the
diaphragm (key 56) is not pinched,
twisted or wrinkled while compressing
between the upper and lower diaphragm

21. Lubricate the cap screws (key 57) and nuts
(key 58) and carefully insert through holes in the
outer ange of the diaphragm casings (keys 62
and 63) and diaphragm (key 56). Tighten the cap
screws to the hex nuts to a nal torque value of
27 to 29 ft-lbs / 37 to 39 N•m.
22. Place the control spring (key 68) inside the hole
in the upper diaphragm casing (key 63) or upper
casing welding assembly (key 87) and over the
lower spring guide (key 52). The spring should be
sitting on top of the diaphragm plate (key 55).
23. Lubricate the bore on the top of the upper spring
seat (key 69) where the adjusting screw (key 73)
will make contact. Place the upper spring seat on
top of the control spring (key 68).
24. Install the spring case (key 70) over the control
spring (key 68) and upper spring seat (key 69) and
on top of the spring case spacer (key 66) or upper
casing welding assembly (key 87). Align the holes
in the spring case with the holes in the spring case
spacer or upper casing welding assembly while
ensuring the vent assembly (key 26) is aligned
with valve body inlet.
25. Lubricate cap screws (key 67) and use them
to secure the spring case (key 70) to the spring case
spacer (key 66) or upper casing welding assembly
(key 87). Tighten the cap screws to a nal torque of
25 to 28 ft-lbs / 34 to 38 N•m.